Scaler question, how does it work? (1 Viewer)

[SteveLeach]

I know there is a question in here somewhere.

From what I've been able to find, if I wanted to run a constant height FP image. I'd have to use a scaler of some type.

That way I could purchase a 2.35 ratio screen and for any image ratio unto a 2.35 all I would need to do would be to open or close the curtains a little to expose more or less screen. Pretty must just like the local megaplex's do. And I wouldn't get any letter box bars until a film required a larger ratio, like say the 1959 version of Ben Hur which is reported to be 2.76.


Measured in inches
Ratio----Height---Width---Diag
1.33:1---36.0-----47.9----59.9
1.78:1---36.0-----64.1----73.5
2.35:1---36.0-----84.6----91.9

Lets say my FP has a native 1.78 or (16x9)aspect ratio, with 1280x720 pixels. To me that means that any image ratio up to a ratio of 1.78:1. Will use either some portion of, or all of the display resolution.

Now if I watch Star Wars/Phantom Menace with an aspect ratio of 1.78. Without a scaler, no problem, I'd see the black letterbox bars that we all love to hate.

But with a scaler what happens? I'm guessing that the scaler adjusts the image somehow and that I would then need to either zoom out or in with the FP to get the image to again fit on the screen with a height of 36 inches and no letterbox bars.

Realizing there is no free lunch, what am I missing? Is the scaler still using the full display resolution of 1280x720? Wouldn't that make the image look tall and skinny? Would a different lens be required?

 

[John S]

Not sure exactly what you mean. But I don't know anybody that attempts to get full res out of any of their projectors when displaying wider than widescreen. I even know one or two that leave their projectors in 4:3 and still don't worry about it when displaying widescreen or even full HD. I knwo a few that will zoom the image on their palyer just cropping a tad to fill their 1.78:1 screens.

The curtain (masks) work great though, never see a black bar again.

Interesting on a 16:9 display, generally anything from 1.66:1 to 1.85:1 will have no black bars, in other words, close enough perhaps.

 

[Mark Techer]

The only way to do it is to use an anamorphic lens and a 16:9 projector. A scaler is not needed, but will benefit your image quality. The needed horizontal squeeze will be provided by the DVD player (when set to 16:9), the display can display the image tall and thin (no black bars) and the anamorphic lens restores the geometry by optically stretching the image instead of electrically stretching the image in the display. This way the full panel can be used to give brighter images that use the full vertical rez of the projector...HERE is my 2.35:1 Constant Image Height Set-Up that does not use a video scaler, but rather the DVD player, projector and lens combination...

Mark